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Objective To investigate the effect of trabeculectomy combined with segmental iridectomy, mitomycin C (MMC) and viscoelastic agents usage on the treatment of glaucoma secondary in uveitis. Methods According to the age, degree of inflammation and the condition of Tenon capsule of patients, differ-ent concentration of MMC (0.25-0.33 mg/ml) was used during the operation, with separation of the anterior and posterior synechia, resection of pupillary organization membrane using viscoelastic agents. Segmental iridec-tomy and releasable sutures were also performed on the patients. The visual acuity of preoperation and postoper-ation, intraocular pressure, inflammation and the complication were record. Results Forty-two eyes of 38 cases with glaucoma secondary in uveitis were studied, the mean follow-up time was (12.01±3.56) months. The postoperative visual acuity improved in 14 eyes, didn't change in 28 eyes. The postoperative inflammation of anterior chamber disappeared in 35 eyes, relieved in 7 eyes. And the average postoperative intraocular pres-sure (15.20± 4.64) mmHg was significantly lower than the preoperative intraocular pressure (38.37±12.93) mmHg (t = 8.255, P = 0.000). The total success rate was 92.9%. There were no severe complication. Conclusion Trabeculeetomy combined with MMC, viscoelastic agents usage, separation of anterior and poste-rior syneehia, segmental iridectomy and releasable suture could increase the success rate of operation on pa tients with glaucoma secondary in uveitis, decrease the complication and inflammation reaction of operation, and the recurrence of uveitis. 相似文献
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绝对期青光眼视网膜神经纤维层活体影像学观察 总被引:2,自引:0,他引:2
尽管青光眼是多因素疾病,但最终均为视网膜神经节细胞的凋亡、变性和视神经的损害。Quigiey等的研究表明,青光眼患者的视网膜神经节细胞(RGC)丢失40%左右将出现临床可检测的视野损害。然而,临床绝对期青光眼视功能完全丧失时RGC是否完全丧失?本研究应用光学相干断层扫描仪(optic coherence tomograph,OCT)对绝对期青光眼的视网膜神经纤维层(retinal nerve fiber layer,RNFL)进行了定量观察,以间接了解RGC在绝对期青光眼患者的丢失情况。 相似文献
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目的 运用超声心动图技术对中国高危孕妇的胎儿心脏结构、血流动力学的时相性变化特征进行探测,了解其在胚胎心脏发育中动态变化的规律;对选择性样本的胎儿先天性心脏畸形及其他心脏异常的检出率进行描述性研究。方法 1998~1999年间,对233例胎龄19~39周的胎儿,运用前瞻性研究设计,采用国际标准的详细化超声心动图方法对胎儿的心脏结构和血流动力学特征进行了系统探测。结果 满意获取了各胎龄期心房、心室、主动脉、肺动脉的内径参数,左、右心室内径基本相同,各类参数与胎龄显示高度的正相关关系。整个胎儿阶段二尖瓣、三尖瓣血流模式中a峰始终占主导地位,a、e峰的比例随胎龄增长呈现缓慢下降趋势。主动脉、肺动脉口流速在不同胎龄期的变化无显著意义。超声诊断疑有先天性心脏畸形胎儿的病理检查或生后检查显示,本组人群先天性心脏病检出率为13例(5.7%),以复杂畸形为多数。同时发现14例有心律紊乱占6%,房性早搏占多数。结论 胎儿超声心动图可用以非创伤性的探测胎儿各期的心腔和大血管的内径,以及血流动力学的特征,这不仅对了解不同胎儿时期心脏正常的解剖和生理发育特征有直接的实践意义,而且对胎儿先天性心脏病的筛查和诊断提供了有效的手段。 相似文献
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维生素C、维生素E、硒与镉联合作用对LLC-PK1细胞脂质过氧化的影响 总被引:2,自引:0,他引:2
[目的]研究氯化镉(CACl2)及其分别与维生素C(VitC)、维生素E(VitE)、硒联合作用对猪肾近曲小管上皮(LLC—PKl)细胞增殖、脂质过氧化及抗氧化酶的影响。[方法]实验设对照组、镉组、镉 Vitc组、镉 VitE组和镉 硒组。以四甲基偶氮唑盐(MTT)比色法检测LIE—PK,细胞活力的变化,黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活力,以催化还原性谷胱甘肽(GSH)速度表示谷胱甘肽过氧化物酶(GSH—Px)的活力,硫代巴比妥酸法(TBA)测定丙二醛(MDA)含量。[结果]不同浓度cdcl2(0—100μmol/L)作用于LIE—PK1细胞12h,细胞存活率随CAC12浓度升高而下降,呈剂量一反应关系;VitC 镉组、vitE 镉组、硒 镉组分别与单独加镉组相比均可显著提高LIE—PK,细胞存活率;10—40pmol/L(ktCl2作用LLC—PK,细胞12h后的培养液上清MDA含量明显增加,与对照组相比差别有显著性。同时,CuZn-SOD、Mn-SOD、GSH—Px活力较对照组相比显著性升高;硒 镉组细胞培养液上清MDA含量与镉组相比有显著性下降。[结论]镉对LIE—PKl细胞增殖有明显的抑制作用;镉可引起LIE.PK1细胞脂质过氧化,是导致肾细胞毒性机制之一;硒对镉引起的ILC—PK。细胞的脂质过氧化有一定的拮抗作用。 相似文献
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Objective To compare difference of the cross-sectional pathological imaging and quantitative measurement of central serous chorioretinopathy (CSC) between time-and fourier-domain optical coherence tomography (OCT). Methods Consecutive 26 patients (26 eyes) with unilaterial CSC were subsumed. Bilateral eyes of all the patients underwent time-and fourier-domain OCT. Horizontal and vertical line scanning and radial six-line scanning protocols were used for time-domain OCT examination; horizontal and vertical high resolution five-line scanning and macular cube scanning protocols were used for fourier-domain OCT examination. The characteristics of OCT images, retinal segmentation and the quantitative measurement were compared between these two methods. Results Fourier-domain OCT could yield the three-dimensional images of surface of inner limiting membrane (ILM) and RPE. The band of external limiting membrane (ELM) of normal subjects and CSC patients, and the inner segment and outer segment (IS/OS) of normal subjects could be clearly shown by fourier-domain OCT. However, the band of IS/OS disappeared in 65.4 % of the CSC patients. The outer boundary of retina was defined in front of the retinal pigmental epithelia (RPE) by fourier-domain OCT. The foveal thickness of normal subjects and CSC patients was (180. 50 ±12.69) and (158. 41 ± 34.20) μm, respevtively. The height of detachment of neuralepithelial layer was (245.84± 154.61) μm measured by fourier-domain OCT. The band of IS/OS of normalsubjects could be clearly shown by time-domain OCT. However, the band of IS/OS disappeared in 73.4%of the CSC patients, which showed no difference with fourier-domain OCT (Z=-0. 108, P=0. 914). Theouter boundary of retina was defined in front of the IS/OS band by OCT. The foveal thickness of normal subjects was (141.16±12.75) μm, which was thinner than that measured by fourier-domain OCT (t= 20. 671,P= 0. 000). The foveal thickness and the height of detachment of neural epithelial layer was (146.40± 36.28) μm and (240. 32±156. 82) μm measured by time-domain OCT, respectively, which showed no significant difference with which measured by fourier-domain OCT (t value was from 0. 026 to 1. 517, P value was from 0. 144 to 0. 980). Conclusions Fourier-domain OCT yields better visualization of intraretinal layers and more accurate definition of outer boundary of retina than time-domain OCT. Thus the measurements by fourier-domain OCT were more accurate. Moreover, three-dimensional images of CSC shown by fourier-domain OCT enable the comprehensive observation of pathological morphology and location. 相似文献
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三种仪器测量中央角膜厚度的比较 总被引:3,自引:0,他引:3
[目的]探讨光学相干断层扫描仪(OCT)、超声波角膜测厚仪及OrbscanⅡ角膜地形图/角膜测厚系统(OrbscanⅡ系统)测量中央角膜厚度(CCT)的差异及测量的可重复性.[方法]分别用OCT、超声波角膜测厚仪和OrbscanⅡ系统测量近视患者34例(68只眼)的CCT并对测量值进行比较,用相关分析方法分析不同仪器间测量值的相关性;随机选择15例(30只眼)用三种仪器依次重复测量中央角膜厚度3次,采用方差分析方法分析3种仪器重复测量值的方差.[结果]OCT、超声波角膜测厚仪、OrbscanⅡ系统测得的CCT平均值分别为(515±33)μm、(535±35)μm和(534±44)μm,OCT的测量值比超声波角膜测厚仪与OrbscanⅡ的测量值小,差异有统计学意义(P值分别为0.004和0.003),超声波角膜测厚仪与OrbscanⅡ的测量值差异无统计学意义(P=0.900).OCT测量的CCT值与超声波角膜测厚仪(r=0.980,P<0.001)和OrbscanⅡ系统(r=0.963,P<0.001)测量的CCT值呈正相关.OCT、超声波角膜测厚仪、OrbscanⅡ系统CCT重复测量值的方差分别为(3.75±3.05)、(6.53±3.02)和(5.26±2.98).OCT的方差与超声波角膜厚度测量仪比较差异有统计学意义(P=0.001),与OrbscanⅡ系统比较差异无统计学意义(P=0.083).[结论]OCT测量的CCT值最小;OCT与超声波角膜测厚仪和ObscanⅡ系统对CCT测量值的相关性较好;OCT测量CCT的可重复性较好,可以作为中央角膜厚度测量的工具. 相似文献
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[目的]探讨眼前段异物的UBM图像特征及其应用价值.[方法]应用UBM对39例(39只眼)可疑眼前段异物患者进行检查,分析UBM图像特征,并进行定量测量,同时进行常规X线检查.[结果]UBM显示39例患者均有眼前段异物存留,而X线照片则仅提示27例异物存留.异物的UBM图像均显示为高强反射特征,其中22例同时具有"慧尾征"的超声伪影;异物最大直径为3.93 mm,最小直径为0.21 mm,平均0.94±O.69 mm.39例患者通过异物磁吸术或联合眼内手术取出异物;其中铁异物26例,铜异物3例,铝异物1例,石头异物5例,玻璃异物2例,睫毛异物1例,植物花刺1例.[结论]眼前段异物UBM图像呈高强反射特征,部分同时具有"慧尾征"超声伪影.UBM能准确地判断异物的位置、大小及其与周围组织的关系;对眼前段异物的诊断优于X线检查;为异物的术前定位及手术方式的选择提供客观依据. 相似文献
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